Java library is just a collection of classes that have been written by somebody else already. You download those classes and tell your computer about them, and then you can use those classes in your code. Check out some of these popular Java libraries Java Developer should know in 2023:
RxJava library is an implementation of Java VM using Observables. This popular library extends the Observer Pattern to facilitate efficient event-driven programming by adding composable operators based on the sequence of events or data through a declarative way.
Since HTTP is the most widely used Application layer protocol, there exist several powerful Java-based HTTP client libraries. OkHttp is the simplest but powerful HTTP client library in the JVM. It comes with an easy and clean API to build an HTTP client in Java.This robust Java library supports high-end features like response caching, GZIP shrink,Connection pooling, modern TLS features, etc.
Traditional client-server communications are unidirectional. Java WebSocket is a bi-directional communication protocol used for one TCP connection. This Java library is an essential WebSocket server-client implementation in the Java Web Application Development process. If you’re working with WebSocket, then you should try using this library.
Liquibase is one of the popular Java libraries that support version controlling, tracking, and deployment of SQL database changes in Java-based applications. If your SQL database keeps changing, this tool can significantly simplify and ease out your database migration process.
MapStruct library is a code generator that does mapping between POJO/Bean based on a convention over configuration methodology. The mapping code generated through this tool employs plain method invocations and therefore is quick, type-safe, and understandable.
Mockito is the most popular and widely used mocking Java library. This library is ideal for testing a simple, large, or complex Enterprise Java project. Moreover, Mockito provides a very clean and simple API and keeps the Unit/Integration tests neat and clean.